1. Field of the Invention
The present invention is directed to a closed granular chemical handling system having a dispensing valve mounted to a chemical package and a receiving valve mounted to an application means. When the two valves are coupled to one another they automatically open to provide a path through which chemical can flow from the package to the application means. In addition, when the two valves are uncoupled from one another they both automatically close.
2. Description of the Prior Art
Agricultural planters are used for planting seeds in a field. Typically seeds are stored in a hopper and are dispensed from the hopper by a seed meter. To minimize the number of passes a farmer is required to make, a planter is typically provided with additional hoppers for holding fertilizer or granular chemical pesticides. These hoppers are provided with chemical meters for controlling the flow of fertilizer and pesticide onto the field.
Some planters having a plurality of planting units are provided with a cross auger for directing granular fertilizer from a side loading point to individual hoppers. Liquid fertilizers have also been directed to individual tanks on a planter. In the liquid fertilizer system, as disclosed in U.S. Pat. No. 4,244,522, to Hartwig, liquid fertilizer in a mobile tanker is pumped through a hose to a manifold located on the planter. The hose is coupled to the planter at a coupling valve.
In many instances it is desirable for agricultural workers not to directly handle certain agricultural treatment agents, such as herbicides, insecticides or fertilizers. These agricultural treatment agents are typically delivered to the agricultural workers in sealed containers which must be opened to direct the chemicals to the hopper located on the planter.
To minimize exposure to these chemicals, many times it is recommended for agricultural workers to wear various items of protective clothing, such as rubber gloves and respirators, when loading the planter with these chemicals. After a planting opera on, some of the chemical packages may still contain unused chemicals. The empty packages and the remaining chemical must be stored or disposed of in an approved method.
Typical valve systems for controlling the feed of a product from a container are disclosed in the following U.S. Pat. No. 4,489,858, to Pritchitt, U.S. Pat. No. 4,164,307, to Inamura et al, U.S. Pat. No. 3,543,814, to Aluotto, U.S. Pat. No. 3,446,403, to Serio, U.S. Pat. No. 3,296,649, to Schwartzman, U.S. Pat. No. 3,187,965, to Bourget, U.S. Pat. No. 2,975,465, to Lerner et al, U.S. Pat. No. 2,210,206, to Fisher, U.S. Pat. No. 2,182,878, to Pipenhagen, U.S. Pat. No. 1,934,197, to Mackay et al, and U.S. Pat. No. 1,257,910, to Meves. The devices disclosed in the above-identified patents illustrate container valve assemblies mounted to the discharge openings of their respective containers for controlling the discharge of diverse materials such as powders, powdered soap, cleaning fluid, cosmetics, shoe polish, milk, coffee, and toner for copying machines. The Pipenhagen patent is of particular interest in that it discloses a portable container and valve system for manually applying granular agricultural materials, such as fertilizers, in a home gardening procedure.
None of the devices disclosed in the above identified patents are directed to a safe handling system for large scale application of commercial quantities of granular agricultural treatment material from a container. Moreover, the devices disclosed by the above-identified patents do not teach or suggest a system in which a dispensing valve assembly is adapted to interact with a complimentary receiving valve assembly on a hopper to assure that product will not flow from the container until the container is properly mounted to the hopper structure. The prior art does not recognize a system in which a dispensing valve interacts with a hopper mounted receiving valve having a time delay between the opening and closing of the valves to assure proper flow of the product and prevent leakage of the product before the container is removed from the hopper.